Latch



.May 4,1926.

C. LEDIN ET AL- LATCH Filed March 15, 1925' 61cm mugs Patented May 4, 1926.

Units! STATES- 1,533,401 PATENT GFFECE.

oHAnLEs LnmN AND KARL A. BRKiJ'NINGbOF STAMFORD, CONNECTICUT, ASSIGNORS To'r'HEYA E & TowNn MANUFACTURING COMPANY, or s'rAivzronn, GONNECTI- OUT.

To all whom it may concern: I Be it-known that we, CHARLES LEDIN and KARL A. BnlioNiNG, citizens of the United States, residents of Stamford, in the county of Fairfield and State of Connecticut, have invented certain-new and useful Improvements in Latches; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements in latches and more particularly to those of the rim type,-one object of the invention being to provide improved dead-locking means for the latch bolt.

A further object is to provide dead-locking means for a latch operable by a knob or key to project the bolt or latch a short distance and then dead-lock the same in such manner that it may be sub-. sequently retracted by operation of the knob or key; thus preventing the latch bolt from being forced back by a tool but at the same time permitting the normal operation of the same by the knob or key.

With these and other objects our invention consists in certain novel features of construction and combinations of parts as hereinatter set forth and pointed out in the claims.

In the accompanying drawings,

Figure 1' is a view of a rim lock, with the cover plate separated from the casing, the parts of the mechanism being shown in nor- .mal positions.

Figure 2 is a face view, with the cover plate removed, showing the dead-locking devices in dead-locking position, and

Figure 3 is a sectional view.

The casing of a. rim lock is shown at 1 and its cover plate at 2.. A latch bolt 3 is mounted in the casing and is normally projected by a spring 4,said latch bolt being formed with an opening 5 and provided with shoulders 6-7, with which a dead-lock ing or retaining device 8 may cooperate to lock the bolt against operation by a knob or The dead-locking means which constitute the subject matter of our present invention are such that the latch bolt may be deadlocked and still permit the latch-bolt to be retracted by the operation of a. knob or bolt which shall be,

LATCH.

Application filed March 13, 1925. Serial ire-15,324.

proper key and these devices will now be explained:

opening whereby a bearing may be provided for the shank of aknob 9 and around the mounting of said knob, an annular groove 10 is formed, this groove being interrupted at one point by a lug which forms a stop member 11. The knob carries a roll-back arm 12, from one end portion of which a pin 13 projects and passes through an elongated slot 14 in the rear portion of the latch bolt 3. Near its other end the roll-back arm is formed or provided with a projection 15 which is cooperable with the stop 11 to limit the movement of said arm in one direction. The casing carries, at respective sides of the The casing 1 is made with an.

latch bolt, posts or supports 16 on which a spring 17 is mounted,the free ends 18 of said spring bearing against lugs 19 fixed to the casing. The intermediate portion of the spring 17 is so bent as to form a retaining seat 20 for the pin 13 on the roll-back arm. A roll-back 21 to be operated by a'suitable key actuated means, is mounted in the cover plate 2 of the casing and carries a roll-back cam 22 for cooperation with the pin 13.

When the roll-back arm 12 is moved backwardly by operation of the knob or by a key, the pin 13 will cause the latch bolt to be moved forwardly a short distance and then said pin will ride into the retaining seat 20 of the spring 17,such movement of the roll-back arm 12 being limited by engagement of the projection 15 with the stop 11. The roll-back arm 12 will be retained in the position above described by the action of the spring and the pin 13 and its mounting will bear dead center relation to the axis of the latch bolt, thus dead-locking the latter and preventing it from being pushed .back with the use of a picking tool, but the construction is such that the latch bolt may be retracted by the operation of the knob or withthe use of a proper key.

Having fully described our invention what We claim as new and desire to secure by Letters Patent, is: a

1.' The combination with a latch bolt, a roll-back arm provided near one end with a pin, and means for operating said rollback arm, of a retaining sprin to hold said roll-back arm and pin in axial alignment position where its gin is in dead-locking relation to the latch It 7 p Y 2. In avlatch structure,.the combination of a' casing, a spring actuated latch bolt 'roll-back arm provided with a projection,

and a'stopin'the casing to be engaged by 7 said projection when the 'pin on the roll-back arm is in the seat in the spring and in axial alignment with the latch. bolt and the mounting of said roll-back arm.

'same and the roll-back 3. In a latch structure, the combination of a casing and a' latch bolt mounted therein, said casing having an annular grooveand a stop in said groove, a roll-back arm provided at one end with a pin and near its other end with a proiection movable in said groove and cooperab e with the stop therein, said pin havlng cooperative relation to the latch bolt, and a spring member having a retaining seat for said pin to hold the arm in axial alignment with the latch bolt.

In testimony whereof, we have signed this specification.

CHARLES LEDIN.

- KARL A. BRKUNING. 

